1. Field of the Invention
This invention relates to the treatment of fuel oils, and is directed more particularly to the reduction is size of asphaltene particles in fuel oils, so as to render the fuel oils more suitable for clean combustion.
2. Description of the Prior Art
U.S. Pat. No. 4,109,318 to Hutchins discloses an in-line blender having blades of graduated configuration placed along a central shaft of a flow conduit. The blades form continuous spiral mixing channels which extend well into the center of the conduit. U.S. Pat. No. 4,123,178 to Salzman, et al, discloses a similar in-line blender. In each of the above patents, a number of blades are mounted on a central shaft to impart a general swirl-type motion to a liquid travelling therethrough. Reversal of the direction of swirl is recognized as a mixing expedient.
Numerous other static devices are disclosed in the art as contributing some desirable property to a liquid flowing therethrough. See, for example, U.S. Pat. Nos. 4,441,823; 3,582,048; 4,427,030, and the like.
U.S. Pat. No. 4,479,805 to Batra discloses pumping of an asphaltene-bearing oil through a perforated pipe to reduce the particle size of the asphaltene, particularly when the asphaltene is carried in water-oil emulsions. Notwithstanding the process of Batra, it has been found that the variety of asphaltene in oil renders still further improvements in asphaltene conditioning desirable, in order to reduce particulate emissions from stack gas.
An additional aspect of the commercial background of the invention is the fact that heavy fuel oils have had varying and increasing amounts of asphaltene therein, and the quantity and quality of asphaltene can vary considerably from shipment to shipment.